Struct QueryCachePolicy 

pub struct QueryCachePolicy { /* private fields */ }

Reusable cache metadata for one database query result.

QueryCachePolicy contains the database-neutral parts of query result caching: diagnostic name, logical key, invalidation tags, and optional TTL. It is intentionally independent of SQLx, Diesel, SeaORM, or any other database client.

Example

use std::time::Duration;

use hydracache_db::QueryCachePolicy;

let policy = QueryCachePolicy::named("load-user")
    .key("user:42")
    .tag("user:42")
    .ttl(Duration::from_secs(60));

assert_eq!(policy.name(), Some("load-user"));
assert_eq!(policy.key_value(), Some("user:42"));
assert_eq!(policy.tags_value(), &["user:42".to_owned()]);
assert_eq!(policy.ttl_value(), Some(Duration::from_secs(60)));

The query_cache_policy! macro provides a shorter declarative form when the policy is known at the call site.

Implementations

impl QueryCachePolicy

pub fn new() -> QueryCachePolicy

Create an empty cache policy.

pub fn named(name: impl Into<String>) -> QueryCachePolicy

Create a cache policy with a diagnostic operation name.

pub fn name(&self) -> Option<&str>

Return the optional diagnostic operation name.

pub fn key_value(&self) -> Option<&str>

Return the logical key, if one has been configured.

pub fn tags_value(&self) -> &[String]

Return configured invalidation tags.

pub fn ttl_value(&self) -> Option<Duration>

Return the optional per-entry TTL.

pub fn with_name(self, name: impl Into<String>) -> QueryCachePolicy

Set or replace the diagnostic operation name.

pub fn key(self, key: impl Into<String>) -> QueryCachePolicy

Set the logical cache key.

pub fn key_builder(self, key: CacheKeyBuilder) -> QueryCachePolicy

Set the logical cache key from a segmented key builder.

pub fn for_entity( self, kind: impl ToString, id: impl ToString, ) -> QueryCachePolicy

Set the logical key and add the same entity invalidation tag.

pub fn for_cache_entity<T>(self, id: <T as CacheEntity>::Id) -> QueryCachePolicy

where T: CacheEntity,

Set the logical key and tags from CacheEntity metadata.

pub fn collection(self, name: impl ToString) -> QueryCachePolicy

Set the logical key and invalidation tag for a collection result.

pub fn tag(self, tag: impl Into<String>) -> QueryCachePolicy

Add one invalidation tag.

pub fn collection_tag(self, name: impl ToString) -> QueryCachePolicy

Add a collection invalidation tag from one escaped key segment.

pub fn tags<I, S>(self, tags: I) -> QueryCachePolicy

where I: IntoIterator<Item = S>, S: Into<String>,

Add several invalidation tags.

pub fn tag_set(self, tags: TagSet) -> QueryCachePolicy

Replace invalidation tags from a reusable TagSet.

pub fn ttl(self, ttl: Duration) -> QueryCachePolicy

Set a per-entry TTL.

Trait Implementations

impl Clone for QueryCachePolicy

fn clone(&self) -> QueryCachePolicy

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for QueryCachePolicy

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for QueryCachePolicy

fn default() -> QueryCachePolicy

Returns the “default value” for a type.

impl PartialEq for QueryCachePolicy

fn eq(&self, other: &QueryCachePolicy) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for QueryCachePolicy

impl StructuralPartialEq for QueryCachePolicy